slight rattle - mk4 gti

[audi-tone]

Hi fellas, been searching everywhere but cant find a real answer;
ever since i upgraded my downpipe to a 2.5" i've had a kind of metallic rattle/buzz on boost. ive taken it to a couple of places and they say its normal but i'm just not sure..
i understand te spool is louder because of the dp but could it be my wastegate loose or even worse could it be the tensioner pulley for the cambelt?!
if anyone has seen anything like this i'd love to hear your thoughts.

cheers

[ope126]

Relax mate, had the same issue in my old MK4 also.

The lower part of the dump pipe was knocking on the heat shield on the steering rack under acceleration, i.e. when the engine twists / rocks...

Fix, bend down some of the heat shield for added clearance and get your self some new engine mounts and an upgraded dogbone mount. Thats what I did, worked for me...

[No457 Snowy]

Hi fellas, been searching everywhere but cant find a real answer;
ever since i upgraded my downpipe to a 2.5" i've had a kind of metallic rattle/buzz on boost. ive taken it to a couple of places and they say its normal but i'm just not sure..
i understand te spool is louder because of the dp but could it be my wastegate loose or even worse could it be the tensioner pulley for the cambelt?!
if anyone has seen anything like this i'd love to hear your thoughts.

cheers

How long has the system been on the car?

Try the fix mentioned above but if it's new and was professionally fitted, maybe take it back to whoever made and fitted the downpipe and get them to check it for fit issues and if it is making contact where it shouldn't be. A properly designed and fitted exhaust should not rattle and should allow for a range of movement under operating conditions. People often knock the price of the systems like APR/Billyboat but I've never had a strange noise or rattle from the APR stainless system.


Cheers,

Snowy

[audi-tone]

thanks fellas, there was an issue with the heatshield at first but thats been fixed; i've also fitted the APR dogbone bush which didnt make a difference (to the noise) at all. it's a really strange noise to explain.. it kinda sounds like a loosish bolt somewhere so i think i'm gonna get under the car today and recheck all the bolts i've fiddled with personally and i'll recheck the heatshields..
also, would it make a difference if some of the weld's are inside the pipe? there was a section he couldn't get to so he welding inside instead of out?? could this cause a harmonic vibration??
(there are no exhaust rattle's inside the cabin..)